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<b>db_create</b>
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<b><pre>
#include &lt;db.h&gt;
<p>
typedef struct __db DB;
<p>
int
db_create(DB **dbp, DB_ENV *dbenv, u_int32_t flags);
</pre></b>
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<b>Description: db_create</b>
<p>The DB handle is the handle for a Berkeley DB database, which may or
may not be part of a database environment.</p>
<p>DB handles are free-threaded if the <a href="../api_c/env_open.html#DB_THREAD">DB_THREAD</a> flag is
specified to the <a href="../api_c/db_open.html">DB-&gt;open</a> method when the database is opened or if the
database environment in which the database is opened is free-threaded.
The handle should not be closed while any other handle that refers to
the database is in use; for example, database handles must not be closed
while cursor handles into the database remain open, or transactions that
include operations on the database have not yet been committed or
aborted.  Once the <a href="../api_c/db_close.html">DB-&gt;close</a>, <a href="../api_c/db_remove.html">DB-&gt;remove</a>,
<a href="../api_c/db_rename.html">DB-&gt;rename</a>, or <a href="../api_c/db_verify.html">DB-&gt;verify</a> methods are called, the handle may
not be accessed again, regardless of the method's return.</p>
<p>The db_create function creates a DB structure that is
the handle for a Berkeley DB database.  This function allocates memory for the
structure, returning a pointer to the structure in the memory to which
<b>dbp</b> refers.  To release the allocated memory and discard the
handle, call the <a href="../api_c/db_close.html">DB-&gt;close</a>, <a href="../api_c/db_remove.html">DB-&gt;remove</a>,
<a href="../api_c/db_rename.html">DB-&gt;rename</a>, or <a href="../api_c/db_verify.html">DB-&gt;verify</a> methods.</p>
<p>The DB handle contains a special field, "app_private", which is
declared as type "void *".  This field is provided for the use of the
application program.  It is initialized to NULL and is not further used
by Berkeley DB in any way.</p>
<p>The db_create method
returns a non-zero error value on failure
and 0 on success.
</p>
<b>Parameters</b> <br>
 <b>dbp</b><ul compact><li>The <b>dbp</b> parameter references the memory into which the returned
structure pointer is stored.</ul>
 <b>dbenv</b><ul compact><li>If the <b>dbenv</b> parameter is NULL, the database is standalone; that
is, it is not part of any Berkeley DB environment.
<p>If the <b>dbenv</b> parameter is not NULL, the database is created
within the specified Berkeley DB environment.  The database access methods
automatically make calls to the other subsystems in Berkeley DB, based on the
enclosing environment.  For example, if the environment has been
configured to use locking, the access methods will automatically acquire
the correct locks when reading and writing pages of the database.</p></ul>
 <b>flags</b><ul compact><li>The <b>flags</b> parameter must be set to 0 or
the following value:
<br>
<b><a name="DB_XA_CREATE">DB_XA_CREATE</a></b><ul compact><li>Instead of creating a standalone database, create a database intended
to be accessed via applications running under an X/Open conformant
Transaction Manager.  The database will be opened in the environment
specified by the OPENINFO parameter of the GROUPS section of the
ubbconfig file.  See the <a href="../ref/xa/xa_intro.html">XA
Introduction</a> section in the Berkeley DB Reference Guide for more information.</ul>
<br></ul>
<br>
<br><b>Errors</b>
<p>The db_create method
may fail and return one of the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>An
invalid flag value or parameter was specified.</ul>
<br>
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<br><b>Class</b>
DB
<br><b>See Also</b>
<a href="../api_c/db_list.html">Databases and Related Methods</a>
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